It's been well-documented that Salt Lake Acting Company has revived their 1998 production of "Master Class" this year because actress Anne Cullimore Decker missed playing the role of Maria Callas, stating that the opera diva was "in her bones."

After watching Decker's performance on Sunday, I find that a bit of Callas has crept into my bones, too. That's the true measure of a great performance: It takes hold of you, lingers with you, changes you.

Analyzing all the elements that make her performance so memorable would take a skill greater than I possess, but I think that, like most things I obsess about, it comes down to the tension of opposites.

There's the tension between Callas' command of her space and the way the students in her master class shrink before her. There's the tension between Callas' outer bravado because of her once great voice and her inner insecurity over its decline. And there's the tension between the adulation she's enjoyed from the public and the lack of love she's experienced on a personal level.

The most riveting part of Decker's performance came during a private reverie as she played both sides of a conversation between Callas and her lover, the billionaire shipping magnate Aristotle Onassis. There was great tension here, too, between the coarse vulgarity of "Ari" and the helpless vulnerability of Callas as she pled for the love he wouldn't give her.

Terrence McNally's 1995 script is based on a series of classes Callas taught at Juilliard between 1971 and 1972. The classes were attended by the curious public as well as students, and this allowed for the naturally engaging device of having Callas address the audience.

While Decker is absolutely at the center of this universe, her performance is superbly supported by David Mong's impeccable direction and the stunning displays of operatic singing from Natalie Blackman, Shane Haag and Stefanie Londino, who play Callas' three students.

Callas was very affected by the performance given by Haag's character, but dismissive of the performance given by Londino's character. This gave me some pause because I thought Londino's vocals were even more compelling than Haag's excellent ones, but this only adds to my fascination with this play. Callas is so driven by emotion and so self-absorbed that we don't know whether we can trust her impartiality.

I also found myself very drawn to the acting performance of Paul Dorgan, who played Manny, Callas' talented accompanist. He had just the right smile of indulgence for Callas' tempestuous ways, and just the right smile of reassurance for her students.

Keven Myhre's set recreated the wood slatted walls of a classroom stage, and Jim Craig's lighting design let it all fade away at the right moments. Dave Evanoff's sound design brought us the sound of Callas' performances during her reveries. There were times when, from my seat all the way on the right side of the Chapel Theatre, that it was a bit hard to catch every word of Decker's monologues over the sound of these recordings, but even that has an explanation in the script; as Callas says at the beginning of the performance, if we can't hear her, we aren't concentrating hard enough.

As a season add-on and fundraiser, "Master Class" has a hefty ticket price -- $50 for non-subscribers -- but it's worth every cent. Performances that linger in your bones are what great theater is all about.